#define DEBUG_TYPE "misched"
#include "llvm/CodeGen/MachineScheduler.h"
-#include "llvm/ADT/OwningPtr.h"
#include "llvm/ADT/PriorityQueue.h"
#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/CodeGen/LiveIntervalAnalysis.h"
static cl::opt<unsigned> MISchedCutoff("misched-cutoff", cl::Hidden,
cl::desc("Stop scheduling after N instructions"), cl::init(~0U));
+
+static cl::opt<std::string> SchedOnlyFunc("misched-only-func", cl::Hidden,
+ cl::desc("Only schedule this function"));
+static cl::opt<unsigned> SchedOnlyBlock("misched-only-block", cl::Hidden,
+ cl::desc("Only schedule this MBB#"));
#else
static bool ViewMISchedDAGs = false;
#endif // NDEBUG
public:
MachineSchedulerBase(char &ID): MachineFunctionPass(ID) {}
- virtual void print(raw_ostream &O, const Module* = 0) const;
+ void print(raw_ostream &O, const Module* = 0) const override;
protected:
void scheduleRegions(ScheduleDAGInstrs &Scheduler);
public:
MachineScheduler();
- virtual void getAnalysisUsage(AnalysisUsage &AU) const;
+ void getAnalysisUsage(AnalysisUsage &AU) const override;
- virtual bool runOnMachineFunction(MachineFunction&);
+ bool runOnMachineFunction(MachineFunction&) override;
static char ID; // Class identification, replacement for typeinfo
public:
PostMachineScheduler();
- virtual void getAnalysisUsage(AnalysisUsage &AU) const;
+ void getAnalysisUsage(AnalysisUsage &AU) const override;
- virtual bool runOnMachineFunction(MachineFunction&);
+ bool runOnMachineFunction(MachineFunction&) override;
static char ID; // Class identification, replacement for typeinfo
char &llvm::PostMachineSchedulerID = PostMachineScheduler::ID;
INITIALIZE_PASS(PostMachineScheduler, "postmisched",
- "PostRA Machine Instruction Scheduler", false, false);
+ "PostRA Machine Instruction Scheduler", false, false)
PostMachineScheduler::PostMachineScheduler()
: MachineSchedulerBase(ID) {
/// Forward declare the standard machine scheduler. This will be used as the
/// default scheduler if the target does not set a default.
-static ScheduleDAGInstrs *createGenericSched(MachineSchedContext *C);
-static ScheduleDAGInstrs *createRawGenericSched(MachineSchedContext *C);
+static ScheduleDAGInstrs *createGenericSchedLive(MachineSchedContext *C);
+static ScheduleDAGInstrs *createGenericSchedPostRA(MachineSchedContext *C);
/// Decrement this iterator until reaching the top or a non-debug instr.
static MachineBasicBlock::const_iterator
return Scheduler;
// Default to GenericScheduler.
- return createGenericSched(this);
+ return createGenericSchedLive(this);
}
/// Instantiate a ScheduleDAGInstrs for PostRA scheduling that will be owned by
return Scheduler;
// Default to GenericScheduler.
- // return createRawGenericSched(this);
- return NULL;
+ return createGenericSchedPostRA(this);
}
/// Top-level MachineScheduler pass driver.
// Instantiate the selected scheduler for this target, function, and
// optimization level.
- OwningPtr<ScheduleDAGInstrs> Scheduler(createMachineScheduler());
+ std::unique_ptr<ScheduleDAGInstrs> Scheduler(createMachineScheduler());
scheduleRegions(*Scheduler);
DEBUG(LIS->dump());
// Instantiate the selected scheduler for this target, function, and
// optimization level.
- OwningPtr<ScheduleDAGInstrs> Scheduler(createPostMachineScheduler());
+ std::unique_ptr<ScheduleDAGInstrs> Scheduler(createPostMachineScheduler());
scheduleRegions(*Scheduler);
if (VerifyScheduling)
return true;
}
+/// Return true of the given instruction should not be included in a scheduling
+/// region.
+///
+/// MachineScheduler does not currently support scheduling across calls. To
+/// handle calls, the DAG builder needs to be modified to create register
+/// anti/output dependencies on the registers clobbered by the call's regmask
+/// operand. In PreRA scheduling, the stack pointer adjustment already prevents
+/// scheduling across calls. In PostRA scheduling, we need the isCall to enforce
+/// the boundary, but there would be no benefit to postRA scheduling across
+/// calls this late anyway.
+static bool isSchedBoundary(MachineBasicBlock::iterator MI,
+ MachineBasicBlock *MBB,
+ MachineFunction *MF,
+ const TargetInstrInfo *TII,
+ bool IsPostRA) {
+ return MI->isCall() || TII->isSchedulingBoundary(MI, MBB, *MF);
+}
+
/// Main driver for both MachineScheduler and PostMachineScheduler.
void MachineSchedulerBase::scheduleRegions(ScheduleDAGInstrs &Scheduler) {
const TargetInstrInfo *TII = MF->getTarget().getInstrInfo();
+ bool IsPostRA = Scheduler.isPostRA();
// Visit all machine basic blocks.
//
Scheduler.startBlock(MBB);
+#ifndef NDEBUG
+ if (SchedOnlyFunc.getNumOccurrences() && SchedOnlyFunc != MF->getName())
+ continue;
+ if (SchedOnlyBlock.getNumOccurrences()
+ && (int)SchedOnlyBlock != MBB->getNumber())
+ continue;
+#endif
+
// Break the block into scheduling regions [I, RegionEnd), and schedule each
// region as soon as it is discovered. RegionEnd points the scheduling
// boundary at the bottom of the region. The DAG does not include RegionEnd,
// The Scheduler may insert instructions during either schedule() or
// exitRegion(), even for empty regions. So the local iterators 'I' and
// 'RegionEnd' are invalid across these calls.
- unsigned RemainingInstrs = MBB->size();
+ //
+ // MBB::size() uses instr_iterator to count. Here we need a bundle to count
+ // as a single instruction.
+ unsigned RemainingInstrs = std::distance(MBB->begin(), MBB->end());
for(MachineBasicBlock::iterator RegionEnd = MBB->end();
RegionEnd != MBB->begin(); RegionEnd = Scheduler.begin()) {
// Avoid decrementing RegionEnd for blocks with no terminator.
- if (RegionEnd != MBB->end()
- || TII->isSchedulingBoundary(llvm::prior(RegionEnd), MBB, *MF)) {
+ if (RegionEnd != MBB->end() ||
+ isSchedBoundary(std::prev(RegionEnd), MBB, MF, TII, IsPostRA)) {
--RegionEnd;
// Count the boundary instruction.
--RemainingInstrs;
unsigned NumRegionInstrs = 0;
MachineBasicBlock::iterator I = RegionEnd;
for(;I != MBB->begin(); --I, --RemainingInstrs, ++NumRegionInstrs) {
- if (TII->isSchedulingBoundary(llvm::prior(I), MBB, *MF))
+ if (isSchedBoundary(std::prev(I), MBB, MF, TII, IsPostRA))
break;
}
// Notify the scheduler of the region, even if we may skip scheduling
Scheduler.enterRegion(MBB, I, RegionEnd, NumRegionInstrs);
// Skip empty scheduling regions (0 or 1 schedulable instructions).
- if (I == RegionEnd || I == llvm::prior(RegionEnd)) {
+ if (I == RegionEnd || I == std::prev(RegionEnd)) {
// Close the current region. Bundle the terminator if needed.
// This invalidates 'RegionEnd' and 'I'.
Scheduler.exitRegion();
continue;
}
- DEBUG(dbgs() << "********** MI Scheduling **********\n");
+ DEBUG(dbgs() << "********** " << ((Scheduler.isPostRA()) ? "PostRA " : "")
+ << "MI Scheduling **********\n");
DEBUG(dbgs() << MF->getName()
<< ":BB#" << MBB->getNumber() << " " << MBB->getName()
<< "\n From: " << *I << " To: ";
}
assert(RemainingInstrs == 0 && "Instruction count mismatch!");
Scheduler.finishBlock();
+ if (Scheduler.isPostRA()) {
+ // FIXME: Ideally, no further passes should rely on kill flags. However,
+ // thumb2 size reduction is currently an exception.
+ Scheduler.fixupKills(MBB);
+ }
}
Scheduler.finalizeSchedule();
}
for (std::vector<std::pair<MachineInstr *, MachineInstr *> >::iterator
DI = DbgValues.end(), DE = DbgValues.begin(); DI != DE; --DI) {
- std::pair<MachineInstr *, MachineInstr *> P = *prior(DI);
+ std::pair<MachineInstr *, MachineInstr *> P = *std::prev(DI);
MachineInstr *DbgValue = P.first;
MachineBasicBlock::iterator OrigPrevMI = P.second;
if (&*RegionBegin == DbgValue)
++RegionBegin;
BB->splice(++OrigPrevMI, BB, DbgValue);
- if (OrigPrevMI == llvm::prior(RegionEnd))
+ if (OrigPrevMI == std::prev(RegionEnd))
RegionEnd = DbgValue;
}
DbgValues.clear();
ScheduleDAGMI::enterRegion(bb, begin, end, regioninstrs);
// For convenience remember the end of the liveness region.
- LiveRegionEnd =
- (RegionEnd == bb->end()) ? RegionEnd : llvm::next(RegionEnd);
+ LiveRegionEnd = (RegionEnd == bb->end()) ? RegionEnd : std::next(RegionEnd);
SUPressureDiffs.clear();
unsigned Offset;
LoadInfo(SUnit *su, unsigned reg, unsigned ofs)
: SU(su), BaseReg(reg), Offset(ofs) {}
+
+ bool operator<(const LoadInfo &RHS) const {
+ return std::tie(BaseReg, Offset) < std::tie(RHS.BaseReg, RHS.Offset);
+ }
};
- static bool LoadInfoLess(const LoadClusterMutation::LoadInfo &LHS,
- const LoadClusterMutation::LoadInfo &RHS);
const TargetInstrInfo *TII;
const TargetRegisterInfo *TRI;
const TargetRegisterInfo *tri)
: TII(tii), TRI(tri) {}
- virtual void apply(ScheduleDAGMI *DAG);
+ void apply(ScheduleDAGMI *DAG) override;
protected:
void clusterNeighboringLoads(ArrayRef<SUnit*> Loads, ScheduleDAGMI *DAG);
};
} // anonymous
-bool LoadClusterMutation::LoadInfoLess(
- const LoadClusterMutation::LoadInfo &LHS,
- const LoadClusterMutation::LoadInfo &RHS) {
- if (LHS.BaseReg != RHS.BaseReg)
- return LHS.BaseReg < RHS.BaseReg;
- return LHS.Offset < RHS.Offset;
-}
-
void LoadClusterMutation::clusterNeighboringLoads(ArrayRef<SUnit*> Loads,
ScheduleDAGMI *DAG) {
SmallVector<LoadClusterMutation::LoadInfo,32> LoadRecords;
}
if (LoadRecords.size() < 2)
return;
- std::sort(LoadRecords.begin(), LoadRecords.end(), LoadInfoLess);
+ std::sort(LoadRecords.begin(), LoadRecords.end());
unsigned ClusterLength = 1;
for (unsigned Idx = 0, End = LoadRecords.size(); Idx < (End - 1); ++Idx) {
if (LoadRecords[Idx].BaseReg != LoadRecords[Idx+1].BaseReg) {
public:
MacroFusion(const TargetInstrInfo *tii): TII(tii) {}
- virtual void apply(ScheduleDAGMI *DAG);
+ void apply(ScheduleDAGMI *DAG) override;
};
} // anonymous
public:
CopyConstrain(const TargetInstrInfo *, const TargetRegisterInfo *) {}
- virtual void apply(ScheduleDAGMI *DAG);
+ void apply(ScheduleDAGMI *DAG) override;
protected:
void constrainLocalCopy(SUnit *CopySU, ScheduleDAGMILive *DAG);
// Check if GlobalLI contains a hole in the vicinity of LocalLI.
if (GlobalSegment != GlobalLI->begin()) {
// Two address defs have no hole.
- if (SlotIndex::isSameInstr(llvm::prior(GlobalSegment)->end,
+ if (SlotIndex::isSameInstr(std::prev(GlobalSegment)->end,
GlobalSegment->start)) {
return;
}
// If the prior global segment may be defined by the same two-address
// instruction that also defines LocalLI, then can't make a hole here.
- if (SlotIndex::isSameInstr(llvm::prior(GlobalSegment)->start,
+ if (SlotIndex::isSameInstr(std::prev(GlobalSegment)->start,
LocalLI->beginIndex())) {
return;
}
// If GlobalLI has a prior segment, it must be live into the EBB. Otherwise
// it would be a disconnected component in the live range.
- assert(llvm::prior(GlobalSegment)->start < LocalLI->beginIndex() &&
+ assert(std::prev(GlobalSegment)->start < LocalLI->beginIndex() &&
"Disconnected LRG within the scheduling region.");
}
MachineInstr *GlobalDef = LIS->getInstructionFromIndex(GlobalSegment->start);
//===----------------------------------------------------------------------===//
// MachineSchedStrategy helpers used by GenericScheduler, GenericPostScheduler
// and possibly other custom schedulers.
-// ===----------------------------------------------------------------------===/
+//===----------------------------------------------------------------------===//
static const unsigned InvalidCycle = ~0U;
IsResourceLimited = false;
ReservedCycles.clear();
#ifndef NDEBUG
+ // Track the maximum number of stall cycles that could arise either from the
+ // latency of a DAG edge or the number of cycles that a processor resource is
+ // reserved (SchedBoundary::ReservedCycles).
MaxObservedLatency = 0;
#endif
// Reserve a zero-count for invalid CritResIdx.
///
/// TODO: Also check whether the SU must start a new group.
bool SchedBoundary::checkHazard(SUnit *SU) {
- if (HazardRec->isEnabled())
- return HazardRec->getHazardType(SU) != ScheduleHazardRecognizer::NoHazard;
-
+ if (HazardRec->isEnabled()
+ && HazardRec->getHazardType(SU) != ScheduleHazardRecognizer::NoHazard) {
+ return true;
+ }
unsigned uops = SchedModel->getNumMicroOps(SU->getInstr());
if ((CurrMOps > 0) && (CurrMOps + uops > SchedModel->getIssueWidth())) {
DEBUG(dbgs() << " SU(" << SU->NodeNum << ") uops="
PI = SchedModel->getWriteProcResBegin(SC),
PE = SchedModel->getWriteProcResEnd(SC); PI != PE; ++PI) {
unsigned PIdx = PI->ProcResourceIdx;
- if (SchedModel->getProcResource(PIdx)->BufferSize == 0)
+ if (SchedModel->getProcResource(PIdx)->BufferSize == 0) {
ReservedCycles[PIdx] = isTop() ? NextCycle + PI->Cycles : NextCycle;
+#ifndef NDEBUG
+ MaxObservedLatency = std::max(PI->Cycles, MaxObservedLatency);
+#endif
+ }
}
}
}
}
else {
// After updating ZoneCritResIdx and ExpectedLatency, check if we're
- // resource limited. If a stall occured, bumpCycle does this.
+ // resource limited. If a stall occurred, bumpCycle does this.
unsigned LFactor = SchedModel->getLatencyFactor();
IsResourceLimited =
(int)(getCriticalCount() - (getScheduledLatency() * LFactor))
// bump the cycle to avoid uselessly checking everything in the readyQ.
CurrMOps += IncMOps;
while (CurrMOps >= SchedModel->getIssueWidth()) {
- bumpCycle(++NextCycle);
DEBUG(dbgs() << " *** Max MOps " << CurrMOps
<< " at cycle " << CurrCycle << '\n');
+ bumpCycle(++NextCycle);
}
DEBUG(dumpScheduledState());
}
#endif
//===----------------------------------------------------------------------===//
-// GenericScheduler - Implementation of the generic MachineSchedStrategy.
+// GenericScheduler - Generic implementation of MachineSchedStrategy.
//===----------------------------------------------------------------------===//
namespace {
-/// GenericScheduler shrinks the unscheduled zone using heuristics to balance
-/// the schedule.
-class GenericScheduler : public MachineSchedStrategy {
+/// Base class for GenericScheduler. This class maintains information about
+/// scheduling candidates based on TargetSchedModel making it easy to implement
+/// heuristics for either preRA or postRA scheduling.
+class GenericSchedulerBase : public MachineSchedStrategy {
public:
/// Represent the type of SchedCandidate found within a single queue.
/// pickNodeBidirectional depends on these listed by decreasing priority.
TopDepthReduce, TopPathReduce, NextDefUse, NodeOrder};
#ifndef NDEBUG
- static const char *getReasonStr(GenericScheduler::CandReason Reason);
+ static const char *getReasonStr(GenericSchedulerBase::CandReason Reason);
#endif
/// Policy for scheduling the next instruction in the candidate's zone.
bool isRepeat(CandReason R) { return RepeatReasonSet & (1 << R); }
void setRepeat(CandReason R) { RepeatReasonSet |= (1 << R); }
- void initResourceDelta(const ScheduleDAGMILive *DAG,
+ void initResourceDelta(const ScheduleDAGMI *DAG,
const TargetSchedModel *SchedModel);
};
-private:
+protected:
const MachineSchedContext *Context;
- ScheduleDAGMILive *DAG;
const TargetSchedModel *SchedModel;
const TargetRegisterInfo *TRI;
- // State of the top and bottom scheduled instruction boundaries.
SchedRemainder Rem;
+protected:
+ GenericSchedulerBase(const MachineSchedContext *C):
+ Context(C), SchedModel(0), TRI(0) {}
+
+ void setPolicy(CandPolicy &Policy, bool IsPostRA, SchedBoundary &CurrZone,
+ SchedBoundary *OtherZone);
+
+#ifndef NDEBUG
+ void traceCandidate(const SchedCandidate &Cand);
+#endif
+};
+} // namespace
+
+void GenericSchedulerBase::SchedCandidate::
+initResourceDelta(const ScheduleDAGMI *DAG,
+ const TargetSchedModel *SchedModel) {
+ if (!Policy.ReduceResIdx && !Policy.DemandResIdx)
+ return;
+
+ const MCSchedClassDesc *SC = DAG->getSchedClass(SU);
+ for (TargetSchedModel::ProcResIter
+ PI = SchedModel->getWriteProcResBegin(SC),
+ PE = SchedModel->getWriteProcResEnd(SC); PI != PE; ++PI) {
+ if (PI->ProcResourceIdx == Policy.ReduceResIdx)
+ ResDelta.CritResources += PI->Cycles;
+ if (PI->ProcResourceIdx == Policy.DemandResIdx)
+ ResDelta.DemandedResources += PI->Cycles;
+ }
+}
+
+/// Set the CandPolicy given a scheduling zone given the current resources and
+/// latencies inside and outside the zone.
+void GenericSchedulerBase::setPolicy(CandPolicy &Policy,
+ bool IsPostRA,
+ SchedBoundary &CurrZone,
+ SchedBoundary *OtherZone) {
+ // Apply preemptive heuristics based on the the total latency and resources
+ // inside and outside this zone. Potential stalls should be considered before
+ // following this policy.
+
+ // Compute remaining latency. We need this both to determine whether the
+ // overall schedule has become latency-limited and whether the instructions
+ // outside this zone are resource or latency limited.
+ //
+ // The "dependent" latency is updated incrementally during scheduling as the
+ // max height/depth of scheduled nodes minus the cycles since it was
+ // scheduled:
+ // DLat = max (N.depth - (CurrCycle - N.ReadyCycle) for N in Zone
+ //
+ // The "independent" latency is the max ready queue depth:
+ // ILat = max N.depth for N in Available|Pending
+ //
+ // RemainingLatency is the greater of independent and dependent latency.
+ unsigned RemLatency = CurrZone.getDependentLatency();
+ RemLatency = std::max(RemLatency,
+ CurrZone.findMaxLatency(CurrZone.Available.elements()));
+ RemLatency = std::max(RemLatency,
+ CurrZone.findMaxLatency(CurrZone.Pending.elements()));
+
+ // Compute the critical resource outside the zone.
+ unsigned OtherCritIdx = 0;
+ unsigned OtherCount =
+ OtherZone ? OtherZone->getOtherResourceCount(OtherCritIdx) : 0;
+
+ bool OtherResLimited = false;
+ if (SchedModel->hasInstrSchedModel()) {
+ unsigned LFactor = SchedModel->getLatencyFactor();
+ OtherResLimited = (int)(OtherCount - (RemLatency * LFactor)) > (int)LFactor;
+ }
+ // Schedule aggressively for latency in PostRA mode. We don't check for
+ // acyclic latency during PostRA, and highly out-of-order processors will
+ // skip PostRA scheduling.
+ if (!OtherResLimited) {
+ if (IsPostRA || (RemLatency + CurrZone.getCurrCycle() > Rem.CriticalPath)) {
+ Policy.ReduceLatency |= true;
+ DEBUG(dbgs() << " " << CurrZone.Available.getName()
+ << " RemainingLatency " << RemLatency << " + "
+ << CurrZone.getCurrCycle() << "c > CritPath "
+ << Rem.CriticalPath << "\n");
+ }
+ }
+ // If the same resource is limiting inside and outside the zone, do nothing.
+ if (CurrZone.getZoneCritResIdx() == OtherCritIdx)
+ return;
+
+ DEBUG(
+ if (CurrZone.isResourceLimited()) {
+ dbgs() << " " << CurrZone.Available.getName() << " ResourceLimited: "
+ << SchedModel->getResourceName(CurrZone.getZoneCritResIdx())
+ << "\n";
+ }
+ if (OtherResLimited)
+ dbgs() << " RemainingLimit: "
+ << SchedModel->getResourceName(OtherCritIdx) << "\n";
+ if (!CurrZone.isResourceLimited() && !OtherResLimited)
+ dbgs() << " Latency limited both directions.\n");
+
+ if (CurrZone.isResourceLimited() && !Policy.ReduceResIdx)
+ Policy.ReduceResIdx = CurrZone.getZoneCritResIdx();
+
+ if (OtherResLimited)
+ Policy.DemandResIdx = OtherCritIdx;
+}
+
+#ifndef NDEBUG
+const char *GenericSchedulerBase::getReasonStr(
+ GenericSchedulerBase::CandReason Reason) {
+ switch (Reason) {
+ case NoCand: return "NOCAND ";
+ case PhysRegCopy: return "PREG-COPY";
+ case RegExcess: return "REG-EXCESS";
+ case RegCritical: return "REG-CRIT ";
+ case Stall: return "STALL ";
+ case Cluster: return "CLUSTER ";
+ case Weak: return "WEAK ";
+ case RegMax: return "REG-MAX ";
+ case ResourceReduce: return "RES-REDUCE";
+ case ResourceDemand: return "RES-DEMAND";
+ case TopDepthReduce: return "TOP-DEPTH ";
+ case TopPathReduce: return "TOP-PATH ";
+ case BotHeightReduce:return "BOT-HEIGHT";
+ case BotPathReduce: return "BOT-PATH ";
+ case NextDefUse: return "DEF-USE ";
+ case NodeOrder: return "ORDER ";
+ };
+ llvm_unreachable("Unknown reason!");
+}
+
+void GenericSchedulerBase::traceCandidate(const SchedCandidate &Cand) {
+ PressureChange P;
+ unsigned ResIdx = 0;
+ unsigned Latency = 0;
+ switch (Cand.Reason) {
+ default:
+ break;
+ case RegExcess:
+ P = Cand.RPDelta.Excess;
+ break;
+ case RegCritical:
+ P = Cand.RPDelta.CriticalMax;
+ break;
+ case RegMax:
+ P = Cand.RPDelta.CurrentMax;
+ break;
+ case ResourceReduce:
+ ResIdx = Cand.Policy.ReduceResIdx;
+ break;
+ case ResourceDemand:
+ ResIdx = Cand.Policy.DemandResIdx;
+ break;
+ case TopDepthReduce:
+ Latency = Cand.SU->getDepth();
+ break;
+ case TopPathReduce:
+ Latency = Cand.SU->getHeight();
+ break;
+ case BotHeightReduce:
+ Latency = Cand.SU->getHeight();
+ break;
+ case BotPathReduce:
+ Latency = Cand.SU->getDepth();
+ break;
+ }
+ dbgs() << " SU(" << Cand.SU->NodeNum << ") " << getReasonStr(Cand.Reason);
+ if (P.isValid())
+ dbgs() << " " << TRI->getRegPressureSetName(P.getPSet())
+ << ":" << P.getUnitInc() << " ";
+ else
+ dbgs() << " ";
+ if (ResIdx)
+ dbgs() << " " << SchedModel->getProcResource(ResIdx)->Name << " ";
+ else
+ dbgs() << " ";
+ if (Latency)
+ dbgs() << " " << Latency << " cycles ";
+ else
+ dbgs() << " ";
+ dbgs() << '\n';
+}
+#endif
+
+/// Return true if this heuristic determines order.
+static bool tryLess(int TryVal, int CandVal,
+ GenericSchedulerBase::SchedCandidate &TryCand,
+ GenericSchedulerBase::SchedCandidate &Cand,
+ GenericSchedulerBase::CandReason Reason) {
+ if (TryVal < CandVal) {
+ TryCand.Reason = Reason;
+ return true;
+ }
+ if (TryVal > CandVal) {
+ if (Cand.Reason > Reason)
+ Cand.Reason = Reason;
+ return true;
+ }
+ Cand.setRepeat(Reason);
+ return false;
+}
+
+static bool tryGreater(int TryVal, int CandVal,
+ GenericSchedulerBase::SchedCandidate &TryCand,
+ GenericSchedulerBase::SchedCandidate &Cand,
+ GenericSchedulerBase::CandReason Reason) {
+ if (TryVal > CandVal) {
+ TryCand.Reason = Reason;
+ return true;
+ }
+ if (TryVal < CandVal) {
+ if (Cand.Reason > Reason)
+ Cand.Reason = Reason;
+ return true;
+ }
+ Cand.setRepeat(Reason);
+ return false;
+}
+
+static bool tryLatency(GenericSchedulerBase::SchedCandidate &TryCand,
+ GenericSchedulerBase::SchedCandidate &Cand,
+ SchedBoundary &Zone) {
+ if (Zone.isTop()) {
+ if (Cand.SU->getDepth() > Zone.getScheduledLatency()) {
+ if (tryLess(TryCand.SU->getDepth(), Cand.SU->getDepth(),
+ TryCand, Cand, GenericSchedulerBase::TopDepthReduce))
+ return true;
+ }
+ if (tryGreater(TryCand.SU->getHeight(), Cand.SU->getHeight(),
+ TryCand, Cand, GenericSchedulerBase::TopPathReduce))
+ return true;
+ }
+ else {
+ if (Cand.SU->getHeight() > Zone.getScheduledLatency()) {
+ if (tryLess(TryCand.SU->getHeight(), Cand.SU->getHeight(),
+ TryCand, Cand, GenericSchedulerBase::BotHeightReduce))
+ return true;
+ }
+ if (tryGreater(TryCand.SU->getDepth(), Cand.SU->getDepth(),
+ TryCand, Cand, GenericSchedulerBase::BotPathReduce))
+ return true;
+ }
+ return false;
+}
+
+static void tracePick(const GenericSchedulerBase::SchedCandidate &Cand,
+ bool IsTop) {
+ DEBUG(dbgs() << "Pick " << (IsTop ? "Top " : "Bot ")
+ << GenericSchedulerBase::getReasonStr(Cand.Reason) << '\n');
+}
+
+namespace {
+/// GenericScheduler shrinks the unscheduled zone using heuristics to balance
+/// the schedule.
+class GenericScheduler : public GenericSchedulerBase {
+ ScheduleDAGMILive *DAG;
+
+ // State of the top and bottom scheduled instruction boundaries.
SchedBoundary Top;
SchedBoundary Bot;
MachineSchedPolicy RegionPolicy;
public:
GenericScheduler(const MachineSchedContext *C):
- Context(C), DAG(0), SchedModel(0), TRI(0),
- Top(SchedBoundary::TopQID, "TopQ"), Bot(SchedBoundary::BotQID, "BotQ") {}
+ GenericSchedulerBase(C), DAG(0), Top(SchedBoundary::TopQID, "TopQ"),
+ Bot(SchedBoundary::BotQID, "BotQ") {}
- virtual void initPolicy(MachineBasicBlock::iterator Begin,
- MachineBasicBlock::iterator End,
- unsigned NumRegionInstrs);
+ void initPolicy(MachineBasicBlock::iterator Begin,
+ MachineBasicBlock::iterator End,
+ unsigned NumRegionInstrs) override;
- bool shouldTrackPressure() const { return RegionPolicy.ShouldTrackPressure; }
+ bool shouldTrackPressure() const override {
+ return RegionPolicy.ShouldTrackPressure;
+ }
- virtual void initialize(ScheduleDAGMI *dag);
+ void initialize(ScheduleDAGMI *dag) override;
- virtual SUnit *pickNode(bool &IsTopNode);
+ SUnit *pickNode(bool &IsTopNode) override;
- virtual void schedNode(SUnit *SU, bool IsTopNode);
+ void schedNode(SUnit *SU, bool IsTopNode) override;
- virtual void releaseTopNode(SUnit *SU) { Top.releaseTopNode(SU); }
+ void releaseTopNode(SUnit *SU) override {
+ Top.releaseTopNode(SU);
+ }
- virtual void releaseBottomNode(SUnit *SU) { Bot.releaseBottomNode(SU); }
+ void releaseBottomNode(SUnit *SU) override {
+ Bot.releaseBottomNode(SU);
+ }
- virtual void registerRoots();
+ void registerRoots() override;
protected:
void checkAcyclicLatency();
- void setPolicy(CandPolicy &Policy, SchedBoundary &CurrZone,
- SchedBoundary &OtherZone);
-
void tryCandidate(SchedCandidate &Cand,
SchedCandidate &TryCand,
SchedBoundary &Zone,
SchedCandidate &Candidate);
void reschedulePhysRegCopies(SUnit *SU, bool isTop);
-
-#ifndef NDEBUG
- void traceCandidate(const SchedCandidate &Cand);
-#endif
};
} // namespace
MachineBasicBlock::iterator End,
unsigned NumRegionInstrs) {
const TargetMachine &TM = Context->MF->getTarget();
+ const TargetLowering *TLI = TM.getTargetLowering();
// Avoid setting up the register pressure tracker for small regions to save
// compile time. As a rough heuristic, only track pressure when the number of
// schedulable instructions exceeds half the integer register file.
- unsigned NIntRegs = Context->RegClassInfo->getNumAllocatableRegs(
- TM.getTargetLowering()->getRegClassFor(MVT::i32));
-
- RegionPolicy.ShouldTrackPressure = NumRegionInstrs > (NIntRegs / 2);
+ RegionPolicy.ShouldTrackPressure = true;
+ for (unsigned VT = MVT::i32; VT > (unsigned)MVT::i1; --VT) {
+ MVT::SimpleValueType LegalIntVT = (MVT::SimpleValueType)VT;
+ if (TLI->isTypeLegal(LegalIntVT)) {
+ unsigned NIntRegs = Context->RegClassInfo->getNumAllocatableRegs(
+ TLI->getRegClassFor(LegalIntVT));
+ RegionPolicy.ShouldTrackPressure = NumRegionInstrs > (NIntRegs / 2);
+ }
+ }
// For generic targets, we default to bottom-up, because it's simpler and more
// compile-time optimizations have been implemented in that direction.
}
}
-/// Set the CandPolicy given a scheduling zone given the current resources and
-/// latencies inside and outside the zone.
-void GenericScheduler::setPolicy(CandPolicy &Policy, SchedBoundary &CurrZone,
- SchedBoundary &OtherZone) {
- // Apply preemptive heuristics based on the the total latency and resources
- // inside and outside this zone. Potential stalls should be considered before
- // following this policy.
-
- // Compute remaining latency. We need this both to determine whether the
- // overall schedule has become latency-limited and whether the instructions
- // outside this zone are resource or latency limited.
- //
- // The "dependent" latency is updated incrementally during scheduling as the
- // max height/depth of scheduled nodes minus the cycles since it was
- // scheduled:
- // DLat = max (N.depth - (CurrCycle - N.ReadyCycle) for N in Zone
- //
- // The "independent" latency is the max ready queue depth:
- // ILat = max N.depth for N in Available|Pending
- //
- // RemainingLatency is the greater of independent and dependent latency.
- unsigned RemLatency = CurrZone.getDependentLatency();
- RemLatency = std::max(RemLatency,
- CurrZone.findMaxLatency(CurrZone.Available.elements()));
- RemLatency = std::max(RemLatency,
- CurrZone.findMaxLatency(CurrZone.Pending.elements()));
-
- // Compute the critical resource outside the zone.
- unsigned OtherCritIdx;
- unsigned OtherCount = OtherZone.getOtherResourceCount(OtherCritIdx);
-
- bool OtherResLimited = false;
- if (SchedModel->hasInstrSchedModel()) {
- unsigned LFactor = SchedModel->getLatencyFactor();
- OtherResLimited = (int)(OtherCount - (RemLatency * LFactor)) > (int)LFactor;
- }
- if (!OtherResLimited
- && (RemLatency + CurrZone.getCurrCycle() > Rem.CriticalPath)) {
- Policy.ReduceLatency |= true;
- DEBUG(dbgs() << " " << CurrZone.Available.getName() << " RemainingLatency "
- << RemLatency << " + " << CurrZone.getCurrCycle() << "c > CritPath "
- << Rem.CriticalPath << "\n");
- }
- // If the same resource is limiting inside and outside the zone, do nothing.
- if (CurrZone.getZoneCritResIdx() == OtherCritIdx)
- return;
-
- DEBUG(
- if (CurrZone.isResourceLimited()) {
- dbgs() << " " << CurrZone.Available.getName() << " ResourceLimited: "
- << SchedModel->getResourceName(CurrZone.getZoneCritResIdx())
- << "\n";
- }
- if (OtherResLimited)
- dbgs() << " RemainingLimit: "
- << SchedModel->getResourceName(OtherCritIdx) << "\n";
- if (!CurrZone.isResourceLimited() && !OtherResLimited)
- dbgs() << " Latency limited both directions.\n");
-
- if (CurrZone.isResourceLimited() && !Policy.ReduceResIdx)
- Policy.ReduceResIdx = CurrZone.getZoneCritResIdx();
-
- if (OtherResLimited)
- Policy.DemandResIdx = OtherCritIdx;
-}
-
-void GenericScheduler::SchedCandidate::
-initResourceDelta(const ScheduleDAGMILive *DAG,
- const TargetSchedModel *SchedModel) {
- if (!Policy.ReduceResIdx && !Policy.DemandResIdx)
- return;
-
- const MCSchedClassDesc *SC = DAG->getSchedClass(SU);
- for (TargetSchedModel::ProcResIter
- PI = SchedModel->getWriteProcResBegin(SC),
- PE = SchedModel->getWriteProcResEnd(SC); PI != PE; ++PI) {
- if (PI->ProcResourceIdx == Policy.ReduceResIdx)
- ResDelta.CritResources += PI->Cycles;
- if (PI->ProcResourceIdx == Policy.DemandResIdx)
- ResDelta.DemandedResources += PI->Cycles;
- }
-}
-
-/// Return true if this heuristic determines order.
-static bool tryLess(int TryVal, int CandVal,
- GenericScheduler::SchedCandidate &TryCand,
- GenericScheduler::SchedCandidate &Cand,
- GenericScheduler::CandReason Reason) {
- if (TryVal < CandVal) {
- TryCand.Reason = Reason;
- return true;
- }
- if (TryVal > CandVal) {
- if (Cand.Reason > Reason)
- Cand.Reason = Reason;
- return true;
- }
- Cand.setRepeat(Reason);
- return false;
-}
-
-static bool tryGreater(int TryVal, int CandVal,
- GenericScheduler::SchedCandidate &TryCand,
- GenericScheduler::SchedCandidate &Cand,
- GenericScheduler::CandReason Reason) {
- if (TryVal > CandVal) {
- TryCand.Reason = Reason;
- return true;
- }
- if (TryVal < CandVal) {
- if (Cand.Reason > Reason)
- Cand.Reason = Reason;
- return true;
- }
- Cand.setRepeat(Reason);
- return false;
-}
-
static bool tryPressure(const PressureChange &TryP,
const PressureChange &CandP,
- GenericScheduler::SchedCandidate &TryCand,
- GenericScheduler::SchedCandidate &Cand,
- GenericScheduler::CandReason Reason) {
+ GenericSchedulerBase::SchedCandidate &TryCand,
+ GenericSchedulerBase::SchedCandidate &Cand,
+ GenericSchedulerBase::CandReason Reason) {
int TryRank = TryP.getPSetOrMax();
int CandRank = CandP.getPSetOrMax();
// If both candidates affect the same set, go with the smallest increase.
return 0;
}
-static bool tryLatency(GenericScheduler::SchedCandidate &TryCand,
- GenericScheduler::SchedCandidate &Cand,
- SchedBoundary &Zone) {
- if (Zone.isTop()) {
- if (Cand.SU->getDepth() > Zone.getScheduledLatency()) {
- if (tryLess(TryCand.SU->getDepth(), Cand.SU->getDepth(),
- TryCand, Cand, GenericScheduler::TopDepthReduce))
- return true;
- }
- if (tryGreater(TryCand.SU->getHeight(), Cand.SU->getHeight(),
- TryCand, Cand, GenericScheduler::TopPathReduce))
- return true;
- }
- else {
- if (Cand.SU->getHeight() > Zone.getScheduledLatency()) {
- if (tryLess(TryCand.SU->getHeight(), Cand.SU->getHeight(),
- TryCand, Cand, GenericScheduler::BotHeightReduce))
- return true;
- }
- if (tryGreater(TryCand.SU->getDepth(), Cand.SU->getDepth(),
- TryCand, Cand, GenericScheduler::BotPathReduce))
- return true;
- }
- return false;
-}
-
/// Apply a set of heursitics to a new candidate. Heuristics are currently
/// hierarchical. This may be more efficient than a graduated cost model because
/// we don't need to evaluate all aspects of the model for each node in the
}
}
-#ifndef NDEBUG
-const char *GenericScheduler::getReasonStr(
- GenericScheduler::CandReason Reason) {
- switch (Reason) {
- case NoCand: return "NOCAND ";
- case PhysRegCopy: return "PREG-COPY";
- case RegExcess: return "REG-EXCESS";
- case RegCritical: return "REG-CRIT ";
- case Stall: return "STALL ";
- case Cluster: return "CLUSTER ";
- case Weak: return "WEAK ";
- case RegMax: return "REG-MAX ";
- case ResourceReduce: return "RES-REDUCE";
- case ResourceDemand: return "RES-DEMAND";
- case TopDepthReduce: return "TOP-DEPTH ";
- case TopPathReduce: return "TOP-PATH ";
- case BotHeightReduce:return "BOT-HEIGHT";
- case BotPathReduce: return "BOT-PATH ";
- case NextDefUse: return "DEF-USE ";
- case NodeOrder: return "ORDER ";
- };
- llvm_unreachable("Unknown reason!");
-}
-
-void GenericScheduler::traceCandidate(const SchedCandidate &Cand) {
- PressureChange P;
- unsigned ResIdx = 0;
- unsigned Latency = 0;
- switch (Cand.Reason) {
- default:
- break;
- case RegExcess:
- P = Cand.RPDelta.Excess;
- break;
- case RegCritical:
- P = Cand.RPDelta.CriticalMax;
- break;
- case RegMax:
- P = Cand.RPDelta.CurrentMax;
- break;
- case ResourceReduce:
- ResIdx = Cand.Policy.ReduceResIdx;
- break;
- case ResourceDemand:
- ResIdx = Cand.Policy.DemandResIdx;
- break;
- case TopDepthReduce:
- Latency = Cand.SU->getDepth();
- break;
- case TopPathReduce:
- Latency = Cand.SU->getHeight();
- break;
- case BotHeightReduce:
- Latency = Cand.SU->getHeight();
- break;
- case BotPathReduce:
- Latency = Cand.SU->getDepth();
- break;
- }
- dbgs() << " SU(" << Cand.SU->NodeNum << ") " << getReasonStr(Cand.Reason);
- if (P.isValid())
- dbgs() << " " << TRI->getRegPressureSetName(P.getPSet())
- << ":" << P.getUnitInc() << " ";
- else
- dbgs() << " ";
- if (ResIdx)
- dbgs() << " " << SchedModel->getProcResource(ResIdx)->Name << " ";
- else
- dbgs() << " ";
- if (Latency)
- dbgs() << " " << Latency << " cycles ";
- else
- dbgs() << " ";
- dbgs() << '\n';
-}
-#endif
-
/// Pick the best candidate from the queue.
///
/// TODO: getMaxPressureDelta results can be mostly cached for each SUnit during
}
}
-static void tracePick(const GenericScheduler::SchedCandidate &Cand,
- bool IsTop) {
- DEBUG(dbgs() << "Pick " << (IsTop ? "Top " : "Bot ")
- << GenericScheduler::getReasonStr(Cand.Reason) << '\n');
-}
-
/// Pick the best candidate node from either the top or bottom queue.
SUnit *GenericScheduler::pickNodeBidirectional(bool &IsTopNode) {
// Schedule as far as possible in the direction of no choice. This is most
SchedCandidate TopCand(NoPolicy);
// Set the bottom-up policy based on the state of the current bottom zone and
// the instructions outside the zone, including the top zone.
- setPolicy(BotCand.Policy, Bot, Top);
+ setPolicy(BotCand.Policy, /*IsPostRA=*/false, Bot, &Top);
// Set the top-down policy based on the state of the current top zone and
// the instructions outside the zone, including the bottom zone.
- setPolicy(TopCand.Policy, Top, Bot);
+ setPolicy(TopCand.Policy, /*IsPostRA=*/false, Top, &Bot);
// Prefer bottom scheduling when heuristics are silent.
pickNodeFromQueue(Bot, DAG->getBotRPTracker(), BotCand);
}
/// Update the scheduler's state after scheduling a node. This is the same node
-/// that was just returned by pickNode(). However, ScheduleDAGMILive needs to update
-/// it's state based on the current cycle before MachineSchedStrategy does.
+/// that was just returned by pickNode(). However, ScheduleDAGMILive needs to
+/// update it's state based on the current cycle before MachineSchedStrategy
+/// does.
///
/// FIXME: Eventually, we may bundle physreg copies rather than rescheduling
/// them here. See comments in biasPhysRegCopy.
}
}
-/// Create a generic scheduler with no DAG mutation passes.
-static ScheduleDAGInstrs *createRawGenericSched(MachineSchedContext *C) {
- return new ScheduleDAGMILive(C, new GenericScheduler(C));
-}
-
/// Create the standard converging machine scheduler. This will be used as the
/// default scheduler if the target does not set a default.
-static ScheduleDAGInstrs *createGenericSched(MachineSchedContext *C) {
- ScheduleDAGMILive *DAG =
- static_cast<ScheduleDAGMILive*>(createRawGenericSched(C));
+static ScheduleDAGInstrs *createGenericSchedLive(MachineSchedContext *C) {
+ ScheduleDAGMILive *DAG = new ScheduleDAGMILive(C, new GenericScheduler(C));
// Register DAG post-processors.
//
// FIXME: extend the mutation API to allow earlier mutations to instantiate
DAG->addMutation(new MacroFusion(DAG->TII));
return DAG;
}
+
static MachineSchedRegistry
GenericSchedRegistry("converge", "Standard converging scheduler.",
- createGenericSched);
+ createGenericSchedLive);
+
+//===----------------------------------------------------------------------===//
+// PostGenericScheduler - Generic PostRA implementation of MachineSchedStrategy.
+//===----------------------------------------------------------------------===//
+
+namespace {
+/// PostGenericScheduler - Interface to the scheduling algorithm used by
+/// ScheduleDAGMI.
+///
+/// Callbacks from ScheduleDAGMI:
+/// initPolicy -> initialize(DAG) -> registerRoots -> pickNode ...
+class PostGenericScheduler : public GenericSchedulerBase {
+ ScheduleDAGMI *DAG;
+ SchedBoundary Top;
+ SmallVector<SUnit*, 8> BotRoots;
+public:
+ PostGenericScheduler(const MachineSchedContext *C):
+ GenericSchedulerBase(C), Top(SchedBoundary::TopQID, "TopQ") {}
+
+ virtual ~PostGenericScheduler() {}
+
+ void initPolicy(MachineBasicBlock::iterator Begin,
+ MachineBasicBlock::iterator End,
+ unsigned NumRegionInstrs) override {
+ /* no configurable policy */
+ };
+
+ /// PostRA scheduling does not track pressure.
+ bool shouldTrackPressure() const override { return false; }
+
+ void initialize(ScheduleDAGMI *Dag) override {
+ DAG = Dag;
+ SchedModel = DAG->getSchedModel();
+ TRI = DAG->TRI;
+
+ Rem.init(DAG, SchedModel);
+ Top.init(DAG, SchedModel, &Rem);
+ BotRoots.clear();
+
+ // Initialize the HazardRecognizers. If itineraries don't exist, are empty,
+ // or are disabled, then these HazardRecs will be disabled.
+ const InstrItineraryData *Itin = SchedModel->getInstrItineraries();
+ const TargetMachine &TM = DAG->MF.getTarget();
+ if (!Top.HazardRec) {
+ Top.HazardRec =
+ TM.getInstrInfo()->CreateTargetMIHazardRecognizer(Itin, DAG);
+ }
+ }
+
+ void registerRoots() override;
+
+ SUnit *pickNode(bool &IsTopNode) override;
+
+ void scheduleTree(unsigned SubtreeID) override {
+ llvm_unreachable("PostRA scheduler does not support subtree analysis.");
+ }
+
+ void schedNode(SUnit *SU, bool IsTopNode) override;
+
+ void releaseTopNode(SUnit *SU) override {
+ Top.releaseTopNode(SU);
+ }
+
+ // Only called for roots.
+ void releaseBottomNode(SUnit *SU) override {
+ BotRoots.push_back(SU);
+ }
+
+protected:
+ void tryCandidate(SchedCandidate &Cand, SchedCandidate &TryCand);
+
+ void pickNodeFromQueue(SchedCandidate &Cand);
+};
+} // namespace
+
+void PostGenericScheduler::registerRoots() {
+ Rem.CriticalPath = DAG->ExitSU.getDepth();
+
+ // Some roots may not feed into ExitSU. Check all of them in case.
+ for (SmallVectorImpl<SUnit*>::const_iterator
+ I = BotRoots.begin(), E = BotRoots.end(); I != E; ++I) {
+ if ((*I)->getDepth() > Rem.CriticalPath)
+ Rem.CriticalPath = (*I)->getDepth();
+ }
+ DEBUG(dbgs() << "Critical Path: " << Rem.CriticalPath << '\n');
+}
+
+/// Apply a set of heursitics to a new candidate for PostRA scheduling.
+///
+/// \param Cand provides the policy and current best candidate.
+/// \param TryCand refers to the next SUnit candidate, otherwise uninitialized.
+void PostGenericScheduler::tryCandidate(SchedCandidate &Cand,
+ SchedCandidate &TryCand) {
+
+ // Initialize the candidate if needed.
+ if (!Cand.isValid()) {
+ TryCand.Reason = NodeOrder;
+ return;
+ }
+
+ // Prioritize instructions that read unbuffered resources by stall cycles.
+ if (tryLess(Top.getLatencyStallCycles(TryCand.SU),
+ Top.getLatencyStallCycles(Cand.SU), TryCand, Cand, Stall))
+ return;
+
+ // Avoid critical resource consumption and balance the schedule.
+ if (tryLess(TryCand.ResDelta.CritResources, Cand.ResDelta.CritResources,
+ TryCand, Cand, ResourceReduce))
+ return;
+ if (tryGreater(TryCand.ResDelta.DemandedResources,
+ Cand.ResDelta.DemandedResources,
+ TryCand, Cand, ResourceDemand))
+ return;
+
+ // Avoid serializing long latency dependence chains.
+ if (Cand.Policy.ReduceLatency && tryLatency(TryCand, Cand, Top)) {
+ return;
+ }
+
+ // Fall through to original instruction order.
+ if (TryCand.SU->NodeNum < Cand.SU->NodeNum)
+ TryCand.Reason = NodeOrder;
+}
+
+void PostGenericScheduler::pickNodeFromQueue(SchedCandidate &Cand) {
+ ReadyQueue &Q = Top.Available;
+
+ DEBUG(Q.dump());
+
+ for (ReadyQueue::iterator I = Q.begin(), E = Q.end(); I != E; ++I) {
+ SchedCandidate TryCand(Cand.Policy);
+ TryCand.SU = *I;
+ TryCand.initResourceDelta(DAG, SchedModel);
+ tryCandidate(Cand, TryCand);
+ if (TryCand.Reason != NoCand) {
+ Cand.setBest(TryCand);
+ DEBUG(traceCandidate(Cand));
+ }
+ }
+}
+
+/// Pick the next node to schedule.
+SUnit *PostGenericScheduler::pickNode(bool &IsTopNode) {
+ if (DAG->top() == DAG->bottom()) {
+ assert(Top.Available.empty() && Top.Pending.empty() && "ReadyQ garbage");
+ return NULL;
+ }
+ SUnit *SU;
+ do {
+ SU = Top.pickOnlyChoice();
+ if (!SU) {
+ CandPolicy NoPolicy;
+ SchedCandidate TopCand(NoPolicy);
+ // Set the top-down policy based on the state of the current top zone and
+ // the instructions outside the zone, including the bottom zone.
+ setPolicy(TopCand.Policy, /*IsPostRA=*/true, Top, NULL);
+ pickNodeFromQueue(TopCand);
+ assert(TopCand.Reason != NoCand && "failed to find a candidate");
+ tracePick(TopCand, true);
+ SU = TopCand.SU;
+ }
+ } while (SU->isScheduled);
+
+ IsTopNode = true;
+ Top.removeReady(SU);
+
+ DEBUG(dbgs() << "Scheduling SU(" << SU->NodeNum << ") " << *SU->getInstr());
+ return SU;
+}
+
+/// Called after ScheduleDAGMI has scheduled an instruction and updated
+/// scheduled/remaining flags in the DAG nodes.
+void PostGenericScheduler::schedNode(SUnit *SU, bool IsTopNode) {
+ SU->TopReadyCycle = std::max(SU->TopReadyCycle, Top.getCurrCycle());
+ Top.bumpNode(SU);
+}
+
+/// Create a generic scheduler with no vreg liveness or DAG mutation passes.
+static ScheduleDAGInstrs *createGenericSchedPostRA(MachineSchedContext *C) {
+ return new ScheduleDAGMI(C, new PostGenericScheduler(C), /*IsPostRA=*/true);
+}
//===----------------------------------------------------------------------===//
// ILP Scheduler. Currently for experimental analysis of heuristics.
public:
ILPScheduler(bool MaximizeILP): DAG(0), Cmp(MaximizeILP) {}
- virtual void initialize(ScheduleDAGMI *dag) {
+ void initialize(ScheduleDAGMI *dag) override {
assert(dag->hasVRegLiveness() && "ILPScheduler needs vreg liveness");
DAG = static_cast<ScheduleDAGMILive*>(dag);
DAG->computeDFSResult();
ReadyQ.clear();
}
- virtual void registerRoots() {
+ void registerRoots() override {
// Restore the heap in ReadyQ with the updated DFS results.
std::make_heap(ReadyQ.begin(), ReadyQ.end(), Cmp);
}
/// -----------------------------------------
/// Callback to select the highest priority node from the ready Q.
- virtual SUnit *pickNode(bool &IsTopNode) {
+ SUnit *pickNode(bool &IsTopNode) override {
if (ReadyQ.empty()) return NULL;
std::pop_heap(ReadyQ.begin(), ReadyQ.end(), Cmp);
SUnit *SU = ReadyQ.back();
}
/// \brief Scheduler callback to notify that a new subtree is scheduled.
- virtual void scheduleTree(unsigned SubtreeID) {
+ void scheduleTree(unsigned SubtreeID) override {
std::make_heap(ReadyQ.begin(), ReadyQ.end(), Cmp);
}
/// Callback after a node is scheduled. Mark a newly scheduled tree, notify
/// DFSResults, and resort the priority Q.
- virtual void schedNode(SUnit *SU, bool IsTopNode) {
+ void schedNode(SUnit *SU, bool IsTopNode) override {
assert(!IsTopNode && "SchedDFSResult needs bottom-up");
}
- virtual void releaseTopNode(SUnit *) { /*only called for top roots*/ }
+ void releaseTopNode(SUnit *) override { /*only called for top roots*/ }
- virtual void releaseBottomNode(SUnit *SU) {
+ void releaseBottomNode(SUnit *SU) override {
ReadyQ.push_back(SU);
std::push_heap(ReadyQ.begin(), ReadyQ.end(), Cmp);
}
projects / oota-llvm.git / blobdiff